world cancer report - iarc

have a poorer prognosis for survival from
endometrial carcinoma than their white
counterparts.
OVARIAN CANCER
< 4.0
Fig. 5.67 The global incidence of ovarian cancer. This cancer occurs predominantly in developed countries.
Definition
The majority of ovarian cancers are carcinomas,
which arise from the surface
epithelium of the ovary.
Epidemiology
About 190,000 new cases and 114,000
deaths from ovarian cancer are estimated
to occur annually. The highest rates are
reported in Scandinavia and Eastern
Europe, the USA, and Canada. Low rates
are found in Africa and Asia (Fig. 5.67).
The risk of epithelial tumours increases
with age, occurring predominantly in periand
postmenopausal women. Tumours of
germinal or embryonic origin are more
frequent in young adults.
Etiology
Although most ovarian cancers are sporadic,
a family history is the single most important
220 Human cancers by organ site
< 5.1
< 7.1
< 10.3
Age-standardized incidence/100,000 population
< 16.1
risk factor for ovarian cancer (5-10% of
cases), risk being increased four-fold in
women with an affected first-degree relative.
Cancer of the ovary is influenced by hormones
and reproductive factors (Reproductive
factors and hormones, p76). Risk is
slightly increased with nulliparity and a personal
history of breast cancer. Decreased
risk follows the use of oral contraceptives. In
contrast, hormonal treatment for infertility
entails an increased risk, whereas treatment
at the menopause is only associated with a
small risk. Early menarche or late
menopause may also entail a slightly
increased risk [18]. Diet plays a role, with
increased risk linked to obesity and height, as
well as some nutritional factors (e.g. lactose).
A history of pelvic inflammatory disease,
polycystic ovary syndrome and endometriosis
have also been associated with increased
risk, whilst tubal ligation and hysterectomy
may decrease risk.
Detection
The great majority of patients with epithelial
ovarian cancer present with disease that has
spread outside of the ovary and even the
pelvis [19]. Symptoms may include abdomi-
Fig. 5.68 Magnetic resonance image (MRI) of a
large, partly cystic ovarian carcinoma.
OC
UT
OC
Fig. 5.69 Surgical specimen of a bilateral ovarian
carcinoma (OC). UT = uterus.
nal discomfort, bloating, abnormal vaginal
bleeding and gastrointestinal or urinary tract
abnormalities. Abdominal and vaginal ultrasonography
may suggest the presence of an
ovarian tumour, but definitive diagnosis
requires laparotomy and biopsy. Pelvic ultrasonography,
tumour markers and clinical
examination have proved ineffective in mass
screening [7] and are employed only for
patients having a high familial risk of ovarian
cancer. The comparison of molecular profiles
generated by laser capture microdissection
is hoped to identify patterns of proteins
which are uniquely expressed in early disease
in order to generate valuable markers
for early detection [20].
Pathology and genetics
Most ovarian tumours are of epithelial origin
and include serous (45% of epithelial
tumours), mucinous, endometrioid (Fig.
5.70) and clear cell adenocarcinomas, as
well as the rare Brenner tumour. Non-epithelial
tumours, including germ cell tumours,
gonadal-stromal tumours and tumours which
have metastasized to the ovary, are less common.
Three categories of lesions are recognized:
benign, low malignancy potential or